Using DDJ-XP2 as a controller

Im looking into the possibilites of using the XP2 as a controller for rekordbox in performance mode. Transport control will work fine as a substitute for jog wheels but ther are a few other key features that Im missing.

* ”back” button for browsing the library

* master deck assign

Are these functions midi mapable and, for the master deck assign, work with deck 3 and 4?